1. Field of the Invention
This invention relates to ammunition and firearms. More particularly, it relates to sabots for spinning tubular projectiles. Still more particularly, it relates to a combustible sabot for a tubular projectile. And, still further it relates to a novel composition and method for making a combustible sabot wherein it is consumed at a rate that substantially coincides with the projectile exit time from the weapon barrel.
2. Description of the Prior Art
Spinning tubular projectiles offer advantages over conventional non-tubular projectiles, among which are flatter trajectory, longer range, shorter flight time and superior penetration of the target.
When a tubular projectile is fired from a gun, it is preferable to plug the opening in the tube with a sabot. Because, the sabot provides surface area against which weapon gases can expand to impart momentum to the projectile. However, once the projectile leaves the barrel, the sabot must be removed in some manner. Removal is usually accomplished either by the sabot being installed in a tubular projectile in such a way that it drops out when the projectile leaves the weapon barrel, or that it be fabricated so that it disintegrates when the projectile leaves the weapon barrel.
A sabot that drops out or disintegrates upon exit from a weapon barrel has a real disadvantage when fired from an aircraft weapon, namely, the drop out or disintegrating sabot may be ingested into the aircraft engine. However, a sabot which completely combusts after having completed its job of providing surface area against which weapon barrel gases can expand leaves no debris to be ingested into an aircraft engine. Thus, combustible sabots are considered essential when the ammunition is to be fired from an aircraft weapon.
The combustible type sabots heretofore were either too weak to maintain the pressure in the weapon barrel, or burn too slowly at the pressure in the breech of the propellant powder, or too difficult or impossible to fabricate wherein the ultimate product is castable after being cured.